Filler cap

ABSTRACT

A filler cap for a motor vehicle fuel tank includes pairs of axially spaced locking and retaining tabs which successively engage the filler neck cam. When the first pair of tabs are disengaged, the second pair engage the cam to prevent direct removal of the cap and permit gradual pressure release from the tank. When the second pair of tabs are disengaged, the cap is completely removable from the filler neck.

United States Patent Brewer 154i FILLER CAP [72] Inventor: Robert W.Brewer, Dayton, Ohio [73] Assignee: General Motors Corporation,

Detroit, Mich.

[22] Filed: Aug. 19, 1971 [2]] Appl. No.: 173,086

[52] US. Cl. ..220/40 R, 220/24 C [51] int. Cl. ..B65d 41/06 [58] Fieldof Search ..220/40 R; 40 S, 24 C [56] References Cited UNITED STATESPATENTS 1,845,409 2/1932 Golden ..220/40 R [1 1' 3,703,245 (451 Nov. 21,1972 1,866,818 7/1032 Reid ..220/40 R Primary Examiner-Raphael N.Schwartz Attorney-J. L. Carpenter et al.

[5 7] ABSTRACT A filler cap for a motor vehicle fuel tank includes pairsof axially spaced locking and retaining tabs which successively engagethe tiller neck cam. When the first pair of tabs are disengaged, thesecond pair engage the cam to prevent direct removal of the cap andpermit gradual pressure release from the tank. When the second pair oftabs are disengaged, the cap is completely removable from the tillerneck.

2 Claims, 4 Drawing Figures PATENTED W21 3.703, 245

I N VEN TOR.

Roberz? [1/ Brewer ATTORNEY FILLER CAP The present invention relates toclosure caps and, in particular, to filler caps for sealing the fillerneck of motor vehicle fuel tank.

Currently, the filler caps for motor vehicle fuel tanks are providedwith means which limit the escape of fuel from the tank. For instance, avalve assembly in the cap controls pressure conditions within the tankto reduce the tendency of the fuel to surge out the tiller neck when thecap is removed.

The present invention minimizes any remaining surging tendency byproviding a cap which must be removed in such a manner that cap removaltime is increased sufficiently to allow complete pressure relief of thetank. This feature is provided by axially spaced pairs of locking andretaining tabs on the filler cap which are sequentially disengaged fromthe filler neck cam by alternate rotary and axial movement. Upon initialopening movement of the cap, the first pair of tabs are disengaged fromthe cam and the cap is axially movable to a venting position wherein thesecond pair of tabs engage the cam and the filler cap cooperates withthe fuel neck to provide restricted venting of the tank. Additionally,the retention of the cap on the neck in cooperation with an elongatedcylindrical flange which surrounds the filler neck opening serves todeflect any surging vapor or liquid fuel. After pressure release fromthe tank, the cap is rotated until the second pair of tabs aredisengaged from the cam and, by additional axial movement, the cap iscompletely removable from the filler neck. By the use of successiveaxial and rotational movements, the cap removal time is extended andexceeds the venting time thereby substantially eliminating surging ofthe fuel out of the filler neck.

The above and other features of the present invention will be apparentto one skilled in the art upon reading the following detaileddescription, reference being made to the accompanying drawingsillustrating a preferred embodiment of the present invention in which:

FIG. 1 is a side elevational view of a motor vehicle fuel tank having afiller neck sealed by a filler cap made in accordance with the presentinvention;

FIG. 2 is an enlarged cross-sectional view of the filler cap in thelocked position on the filler neck;

FIG. 3 is a view similar to FIG. 2 showing the filler cap in anintermediate venting position; and

FIG. 4 is a view taken along line 4-4 of FIG. 2 showing the orientationof the locking tabs.

Referring to FIG. 1, there is shown a motor vehicle fuel tank includingan upwardly projecting filler neck 12 having an opening which is sealedby a filler cap 14. When the cap 14 is removed, the tank 10 is filled ina conventional manner through the filler neck 12. When the filler cap 14is in a locked position, the fuel supply contained within the tank 10subject to pressure relief in a manner described below.

Referring to FIG. 2, the filler neck 12 comprises a pipe whichterminates its upper end with an annular filler base 16. The filler base16 includes a cylindrical sleeve 18 which engages the side of the fillerneck 12, an annular upper seating surface 20, and a downwardlyprojecting cylindrical mouth 22, the inner surface of which defines thefuel opening. As shown in FIG. 3, the mouth 22 is provided with a pairof diametrically opposed downwardly projecting earns 24 which arecircumferentially spaced by axially extending cap withdrawal slots 26.The earns 24 are provided with camming surfaces 28 extending betweenlower detent notches 30 and the withdrawal slots 26. The surface of theslot 26 adjacent the detent 30 defines a stop which limits openingmovement of the cap 14. The notch 30 defines a stop which limits closingmovement of the cap 14.

The filler cap 14 comprises a cover member 32, an internal cup member34, and a valving assembly 36. The valving assembly 36 is conventionalin construction and permits venting of the fuel tank 10 when pressureconditions therewithin exceed a predetermined level. Additionally, thevalving assembly 36 admits air into the tank when vacuum conditionsexceed a predetermined amount.

The cover member 32 includes a circular lid 37 ter minating at its outerdiameter with an elongated downward projecting flange 38 which projectsaxially beyond the lower extremity of the cup member 34. The flange 38surrounds the fuel opening during removal of the filler cap 14 todeflect any vapor and liquid fuel downwardly along the filler neck 12.

As shown in FIG. 3, the cap 14 additionally includes a sealing assembly40 and a handle 42. The sealing assembly 40 comprises an annulardiaphragm 44 and an annular leaf spring 46 which normally biases thediaphragm 44 to a concave shape. The diaphragm 44 and the spring 46 areretained between lid 37 and the cup member 34 and, together with thelocking handle 42, are centrally fixedly attached to the cover 32 by arivet 48. In the locked position, the sealing assembly 40 engages theseating surface 20 on the filler neck 12 thereby sealing the opening. Asthe filler cap 14 is removed, the diaphragm 44 is released from theseating surface 20 to permit restricted pressure release from the tank10.

The cup member 34 includes a cylindrical dome 50 in which the valvingassembly 36 is frictionally retained. Suitable vents 56 are provided inthe cup member 34 for fluidly connecting the valving assembly 36 toatmosphere. The dome 50 is provided at its lower end with pairs ofaxially spaced locking tabs 60 and retaining tabs 62. As shown in FIG.4, the tabs of each pair are diametrically opposed with the tabs 62oriented perpendicular to the tabs 60. Both pairs of tabs arecircumferentially spaced equal to the withdrawal slots 26. However, thetabs may be relatively positioned at any desired angular spacing.

The tabs 60, 62 project radially outwardly from the dome 50 and each areadapted to engage the camming surfaces 28 on the filler neck earns 24.The locking tabs 60 are axially spaced from the cover 32 and the sealingassembly 40 such that when the tabs 60 are in the illustrated lockedposition in the detents 30, the sealing assembly 40 is firmly seatedagainst the seating surface 20. The retaining tabs 62 are axially spacedfrom the locking tabs 60 so as to engage the camming surfaces 28 midwaybetween the detents 30 and the slots 26.

Upon initial opening movement of the filler cap 14, the locking tabs 60ride along the camming surfaces 28 until they register with the slots26. During this rotation, the sealing assembly 40 is axially releasedfrom the seating surface 20 thereby venting the tank 12. The

cap 14 is then axially withdrawn throngh the slots 26 until restrainedby the retaining tabs 62 engaging the camming surfaces 28 at a firstreleased position. This engagement prevents additional axial movement ofthe tiller cap-and provides sufficient additional time for completerelease of fuel tank pressure.

' Thereafter, the cap 14 is additionally rotated until the second set ofretaining tabs 62 register with withdrawal slots 26 at a second releasedposition and the cap 14 is freely removable from the filler neck '12 byadditional axial movement.

Although only one form of this invention has been shown and described,other forms will be readily apparent to those skilled in the art.Therefore, it is not intended to limit the scope of this invention bythe em-' bodiment selected for the purpose of this disclosure but onlyby the claims which follow.

What is claimed is: Y

- 1. A filler capfor a fuel tank filler neck having an opening definedby projecting camming surfaces which are circumferentially spaced byaxiallyextending cap withdrawal slots, said filler cap comprising: acover member including a lid portion; a cup member carried by the lidportion and axially receivable in said opening; outwardly projectinglocking tabs formed on said cup member and axially spaced from said lidportion, said locking tabs being spaced equal to said withdrawal slotsand engaging said camming surfaces upon closing movement of said covermember to seat said cover member against said filler neck, said lockingtabs being disengaged from said camming surfaces at a first releasedposition wherein said locking tabs are aligned with and axiallywithdrawable through said slots; outwardly projecting retaining tabsformed on said cup member and axially spaced thereon remote from saidlocking tabs and said lid portion, said retaining tabs beingcircumferentially spaced equal to said withdrawal slots and beingaxially spaced relative to said locking tabs so as to engage saidcamming surfaces when the cover member is in said first releasedposition thereby preventing direct removal of said cap, said retainingtabs being disengaged from said camming surfaces by additional openingmovement of said cover member to a second released position wherein saidretaining tabs are aligned with the slots and saidcap is fully removablefrom said filler neck.

2; A fuller cap for a fuel tank filler neck having an annular seatingsurface inwardly bounded by a pair of downwardly projecting arcuate camsdefining an axial opening wherein said cams are circumferentially spacedby a pair of axially extending cap withdrawal slots, said filler capcomprising: an annular cover member including a circular lid and adownwardly depending cylindrical flange; sealing means carried by saidlid and engageable with the seating surface to seal the opening; a cupmember connected to said lid and axially receivable in said opening; apair of radially outwardly projecting locking tabs formed on said cupmember, said locking tabs being axially spaced from said lid andcircumferentially spaced equal to said withdrawal slots, said lockingtabs being insertable through said slots and engageable with said camsupon closing movement of said cover member for causing axial advancementof said sealing means toward said seating surface to a closed positionwhereat said sealing means engages said seating surface, said lockingtabs being disengaged from said cams upon opening movement of said covermember 'to a first released position wherein said locking tabs registerwith said slots and are axially withdrawable therethrough, said flangeon said cover member exteriorly encircling said neck and extendingaxially beyond said locking tabs thereby shielding the opening at saidfirst released position and deflecting surging vapor and liquid fuelaway from said opening and downwardly along the neck; a pair of radiallyoutwardly projecting retaining tabs formed on said cup member andaxially spaced remote from said locking tabs and said sealing means,said retaining tabs being circumferentially spaced equal to saidwithdrawal slots and being spaced relative to said-first mentioned tabsso as to axially register with said cams when the locking tabs arewithdrawn beyond said slots thereby preventing direct removal of saidcap and increasing filler cap removal times so as to minimize surging offuel from the tank, said cap being fully removable by additional openingmovement of the retaining tabs to a second released position whereinsaid retaining tabs are aligned with the slots and the cap is removableby additional axial movement.

1. A filler cap for a fuel tank filler neck having an opening defined byprojecting camming surfaces which are circumferentially spaced byaxially extending cap withdrawal slots, said filler cap comprising: acover member including a lid portion; a cup member carried by the lidportion and axially receivable in said opening; outwardly projectinglocking tabs formed on said cup member and axially spaced from said lidportion, said locking tabs being spaced equal to said withdrawal slotsand engaging said camming surfaces upon closing movement of said covermember to seat said cover member against said filler neck, said lockingtabs being disengaged from said camming surfaces at a first releasedposition wherein said locking tabs are aligned with and axiallywithdrawable through said slots; outwardly projecting retaining tabsformed on said cup member and axially spaced thereon remote from saidlocking tabs and said lid portion, said retaining tabs beingcircumferentially spaced equal to said withdrawal slots and beingaxially spaced relative to said locking tabs so as to engage saidcamming surfaces when the cover member is in said first releasedposition thereby preventing direct removal of said cap, said retainingtabs being disengaged from said camming surfaces by additional openingmovement of said cover member to a second released position wherein saidretaining tabs are aligned with the slots and said cap is fullyremovable from said filler neck.
 1. A filler cap for a fuel tank fillerneck having an opening defined by projecting camming surfaces which arecircumferentially spaced by axially extending cap withdrawal slots, saidfiller cap comprising: a cover member including a lid portion; a cupmember carried by the lid portion and axially receivable in saidopening; outwardly projecting locking tabs formed on said cup member andaxially spaced from said lid portion, said locking tabs being spacedequal to said withdrawal slots and engaging said camming surfaces uponclosing movement of said cover member to seat said cover member againstsaid filler neck, said locking tabs being disengaged from said cammingsurfaces at a first released position wherein said locking tabs arealigned with and axially withdrawable through said slots; outwardlyprojecting retaining tabs formed on said cup member and axially spacedthereon remote from said locking tabs and said lid portion, saidretaining tabs being circumferentially spaced equal to said withdrawalslots and being axially spaced relative to said locking tabs so as toengage said camming surfaces when the cover member is in said firstreleased position thereby preventing direct removal of said cap, saidretaining tabs being disengaged from said camming surfaces by additionalopening movement of said cover member to a second released positionwherein said retaining tabs are aligned with the slots and said cap isfully removable from said filler neck.